======================= ISA erasure code plugin

The isa plugin is the default for Ceph erasure coded pools. The isa plugin encapsulates the ISA <https://www.intel.com/content/www/us/en/developer/tools/isa-l/overview.html>_ library.

Create an isa profile

To create a new isa erasure code profile:

.. prompt:: bash $

ceph osd erasure-code-profile set {name}
plugin=isa
technique={reed_sol_van|cauchy}
[k={data-chunks}]
[m={coding-chunks}]
[crush-root={root}]
[crush-failure-domain={bucket-type}]
[crush-device-class={device-class}]
[directory={directory}]
[--force]

Where:

k={data chunks}

:Description: Each object is split in data-chunks parts, each stored on a different OSD.

:Type: Integer :Required: No. :Default: 7

m={coding-chunks}

:Description: Compute coding chunks for each object and store them on different OSDs. The number of coding chunks is also the number of OSDs that can be down without losing data.

:Type: Integer :Required: No. :Default: 3

technique={reed_sol_van|cauchy}

:Description: The ISA plugin comes in two Reed Solomon <https://en.wikipedia.org/wiki/Reed%E2%80%93Solomon_error_correction>_ forms. If reed_sol_van is set, it is Vandermonde <https://en.wikipedia.org/wiki/Vandermonde_matrix>, if cauchy is set, it is Cauchy <https://en.wikipedia.org/wiki/Cauchy_matrix>.

:Type: String :Required: No. :Default: reed_sol_van

crush-root={root}

:Description: The name of the crush bucket used for the first step of the CRUSH rule. For instance step take default.

:Type: String :Required: No. :Default: default

crush-failure-domain={bucket-type}

:Description: Ensure that no two chunks are in a bucket with the same failure domain. For instance, if the failure domain is host no two chunks will be stored on the same host. It is used to create a CRUSH rule step such as step chooseleaf host.

:Type: String :Required: No. :Default: host

crush-device-class={device-class}

:Description: Restrict placement to devices of a specific class (e.g., ssd or hdd), using the crush device class names in the CRUSH map.

:Type: String :Required: No. :Default:

directory={directory}

:Description: Set the directory name from which the erasure code plugin is loaded.

:Type: String :Required: No. :Default: /usr/lib/ceph/erasure-code

--force

:Description: Override an existing profile by the same name.

:Type: String :Required: No.